The likely spill - appearing on images as a grey and white slick - covered waters to the west of the 8-kilometre (5-mile) long island, pictures from Copernicus’s ​Sentinel-1, Sentinel-2 and Sentinel-3 satellites showed on May 6-8.

“The slick ​appears visually consistent with oil,” said Leon Moreland, researcher at ⁠the Conflict and Environment Observatory, who estimated that it was covering ​an area of approximately 45 square km.

Louis Goddard, co-founder of ​consultancy Data Desk, which focuses on climate and commodities, agreed that the images likely showed an oil slick, which he said was potentially the largest to occur ​since the start of the US-Israel war against Iran 70 days ago.

The ​US military and Iran’s mission to the United Nations in Geneva did not immediately ‌respond ⁠to requests for comment on the images.

The cause of the possible spill and the point of origin are currently unknown, Moreland added, noting that images from May 8 showed no evidence of additional active spills.

Kharg Island, where US ​forces said ⁠they had destroyed military targets earlier in the war, is the hub for 90% of Iran’s oil exports, ​much of which is bound for China.

The US ​Navy has ⁠been blockading Iran’s ports in an attempt to stop Tehran’s tankers from entering and exiting, while US and Iranian forces have clashed in the Gulf.

The war ⁠has ​also trapped hundreds of ships in the ​Gulf and caused the world’s biggest disruption to crude oil supply, as well as hitting ​global supplies of oil products and liquefied natural gas.